It's interesting that Toyota and Honda did not find that lead-acid technology "makes better economic sense than anything else". The only hybrid vehicles currently built in any volume use NiMH batteries. I think reliability of these new drivetrains needs to be the first order of business, or they will stumble coming out of the gate. Lower-cost versions can come after reliability has been established.
That said, I think the lead-acid Power Battery would be a decent choice for a gasoline-electric hybrid. I think the nickel-iron Power Battery would be an excellent choice, and would only cost 25% more than the lead-acid version, based on my own estimations some time back.
Thanks for the post! Is this a company you are watching, or did they just show up in a news item? Here is their website, FYI: